


Mindbeast

by Defiler_Wyrm



Category: Captain America (Movies), Captain America - All Media Types
Genre: Anal Fingering, Anal Fisting, Anal Gaping, Anal Sex, Angst with a Happy Ending, BDSM, Bondage, Bottom Bucky Barnes, Breeding Kink, Come Inflation, Dubious Consent, Enemas, Enthusiastic Consent, Forced Orgasm, Gang Rape, Getting Together, HYDRA Trash Party, Happy Ending, Hydra (Marvel), Knotting, Large Cock, M/M, Mating Cycles/In Heat, Monsters, NSFW Art, Not Exactly Bestiality, Object Insertion, Psychic Abilities, Red Room (Marvel), Rimming, Tentacles, Teratophilia, Top Steve Rogers, Touch-Starved, belly torture, medical rape
Language: English
Status: Completed
Published: 2021-01-01
Updated: 2021-01-01
Packaged: 2021-03-10 23:13:25
Rating: Explicit
Warnings: Graphic Depictions Of Violence, Rape/Non-Con
Chapters: 4
Words: 16,248
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28335189
Author URL: https://archiveofourown.org/users/Defiler_Wyrm/pseuds/Defiler_Wyrm
Summary: Hydra has captured something remarkable, and they must take remarkable measures to win its compliance: it’s breeding season for the monster, and they offer up the Winter Soldier to be its mate.The beast and the Soldier meet again, and again, and again.
Relationships: James "Bucky" Barnes/Other(s), James "Bucky" Barnes/Steve Rogers
Comments: 33
Kudos: 211
Collections: Hydra Holiday Trash Party Gift Exchange 2020





	1. One Who Lurks Beneath Snowdrifts

**Author's Note:**

  * For [Lies_Unfurl](https://archiveofourown.org/users/Lies_Unfurl/gifts).



> The prompt I glommed onto was “stomach torture.” I’m not sure how much touch starvation I managed to work into this, but either way, I hope it pleases my giftee. :3
> 
> Major thanks to my beta reader [bluckybleeds](https://archiveofourown.org/users/buckybleeds/pseuds/buckybleeds) for the fantastic feedback!

He is awake.

He is cold.

He is disoriented.

These facts wash over him as he reclines, shivering, in a chair, body convulsing as if he came to at the tail end of a seizure. He _hurts_ , and it’s not the most important thing.

“What is my mission?” he croaks out. Russian is not the language of the first voice in his head, but it is the language of the chorus and refrain.

A severe-looking woman in a uniform glances at him in annoyance, and tells him, “Prep first, orders later. Be quiet, Soldier.”

 _Be quiet_ is his first mission, standing by for further instruction. So he holds back the groans and little whimpers his throat wants to make as he’s manhandled off the chair, allowed to collapse on the floor (his legs don’t work, he notes; this seems like it should be important, but no one else in the room seems to regard it as such), and then forcibly stripped.

He sucks in a sharp breath at how these people’s (he struggles for a word. Technicians?) hands grab and prod and probe him as they peel off the tight vest and pants he had been wearing—but he does not let it back out in a yelp like he wants to. He does not tell them to stop no matter where they touch him. When they jerk him back into position and pinch his skin for flinching away from what they’re forcing on him—what they’re forcing _in_ him—he does not cry out or hiss in discomfort, much less moan with a longing ache he doesn’t understand.

He will complete his orders and remain quiet. They’re testing his resolve, keeping him on hands and knees as a uniformed man with bright blond hair and a thick moustache kneels behind him and drives into his shivering body, and he will not fail.

The man makes quite enough noise for them both, anyway.

It’s over as soon as it starts feeling good. By then his legs have regained enough sensation that he can stand when bidden, and he follows along to the next room, even if it’s with a limp.

This new room makes the hair stand on the back of his neck the moment he sets foot inside. A glance down tells him why: the tile floor is angled downward towards a pair of drains set in the middle. There’s a table with strange arms with metal loops on the ends, surrounded by equipment he can’t identify at a glance. Something with a long hose; a metal table on wheels topped with a tray bearing a weird device and what look like huge, blunt bullets; a jar topped with a pump dispenser; among other things. The Soldier supposes curiosity will get him nowhere in here.

His guards guide him onto the table and soon he finds out what the arms are for. They put his heels into the loops, which forces his legs up and open wide, opening his pelvic floor. It’s uncomfortable being so exposed, but he’s in his masters’ hands, so he doesn’t need to worry about anything they don’t tell him to worry about. Not even when they strap down his ankles, wrists, and upper arms.

“Open him up,” the man who used his body instructs a gaggle of men and women dressed in white with rubber boots. “I’ve started for you already. As much as I would like to watch you work, I must make certain everything will be ready should he meet parameters. Contact me as soon as you have your results.”

“Yes sir,” the technicians chorus.

The blond man turns to leave, then turns back, and comes over to peer down at the Soldier. He places a hand on the Soldier’s inner thigh, idly rubbing his raw, wet hole with a thumb.

“Do you know who I am?”

The Soldier hesitates, then shakes his head.

“I am Major Evgeny Brasiliev,” the man states, “and I am your handler for this mission. I have awaited the chance to have you as my asset with great anticipation for a very long time, and so far you have lived up to your reputation.” He smiles viciously and presses with his thumb. It sinks in easily and draws a gasp. “Don’t let me down.”

With that, he leaves, taking two of the guards and a technician with him.

“Commencing manual preparation,” one of the technicians says. He pumps a gel onto a gloved hand and stands between the Soldier’s splayed legs.

He’s smart enough to see where this is going just before it goes there. After Major Brasiliev’s cock, a single lubed finger isn’t so bad. The gel cools his stinging muscle and brings an unvoiced sigh to his lips. He relaxes and lets it happen. This is also a test, though he’s not sure what they’re testing for. If it was his to know, they would have told him.

Soon one finger becomes two, and the technician pushes them in deep enough to brush something electric, something that makes the Soldier gasp and cough to keep from crying out. Blood rushes to his cock. His hips shift on their own—not away from the stimulation this time, but towards it.

“Note arousal at 3:45, two digits,” the man fingering him says to another the Soldier assumes is taking notes.

“As expected,” someone else says. In a more conversational, even conspiratorial tone the same one mutters, “Pity we don’t have time to have some real fun with him.”

The Soldier is pretty sure he can piece together what “real fun” means in this context. If it’s more like this and less like Major Brasiliev’s idea of getting acquainted, that wouldn’t be so bad.

But the one fingering him says, “It’ll get fun enough when we start the probes. Maybe if we’re _really_ lucky the major will let us play with him when the real test is done.” He hooks his fingers to press on that hot button and the Soldier can’t help it, he mewls quietly, spine bowing up off the table in syrupy pleasure. “That’s good, isn’t it. Good boy.”

“Did you just call the Winter Soldier a good boy?!” a third technician, a woman, says in disbelief.

The first man smirks down at him. “When he’s close to coming from my fingers in his cunt I think I can call him whatever I want.”

“Alright,” a fourth snaps, “keep it professional.”

“Yes sir, sorry sir,” the first and second say, contrite. He pulls his fingers out and the Soldier makes a disappointed noise. “Hose.”

The third technician hands the first a nozzle connected to a long hose, in turn connected to something the Soldier can’t see. He doesn’t have to wonder long what that’s for, as the nozzle goes right up his loosened ass without warning. Its graduated flares act as a stopper, popping subtly as they pass the thick ring of muscle. His muscles flex curiously around its unforgiving length.

“Opening flow, one liter. Soldier, you are to retain this until instructed otherwise. Do you understand?”

The Soldier frowns but nods all the same. He’s not stupid enough to tell Hydra no. “Understood.”

The technician reaches out of view and does something that sounds like turning a valve. The nozzle jumps subtly inside him and then—he jolts bodily as tepid water gushes up into his guts. The order to retain makes more sense now. Is this a cleanup thing? Did the major make him that dirty inside by spilling in him? He frowns up at the ceiling and schools his breathing.

It’s not unpleasant, at first. He actually kind of likes the sensation of liquid surging into him, like a protracted orgasm. As soon as it hits his transverse colon, though, his stomach starts doing flips. He does his best not to squirm, but it’s a near thing.

A few minutes in, the water slows to a trickle, and the technician announces he’s introducing a second liter. The Soldier lets his head fall left to watch as they change out a large, empty water bladder for a full one. There are two more on standby. That doesn’t bode well.

Water rushes in again. Sweat beads up on his chest and brow, slides down his neck into the hollow of his throat, leaves his flesh-and-bone palm clammy. The pressure grows by infinitesimal increments. A soft groan escapes him. To his shock, the technician reaches up and rubs his swollen belly. It doesn’t make anything better, but the confusion over it takes his mind off the discomfort for just a moment. He misses the contact as soon as it’s taken away.

“Two liters complete,” the technician says at last. “Introducing third liter.”

It’s gone from deeply uncomfortable to outright painful at this point. More and more water pumps into his depths. When the Soldier looks down his belly has become visibly swollen—he’s a lean, muscular thing, but it looks like he’s sticking his gut out. His head cracks back onto the table with a dull thud and he groans some more. It’s a sharp pain, like little knives lancing through his intestines as the water forces them open.

“Imminent damage,” he pants. He doesn’t believe the technicians will let him die—he knows, somehow, that he’s far too valuable for that—but he also doesn’t want to find out what a ruptured bowel and the subsequent surgery would feel like.

“You’re fine,” the first technician says flippantly. “You’re almost there, Soldier. Surely you can complete your task instead of voluntarily failing it.”

He scowls, then grimaces, and squirms. The technician is right. It hurts like something is wrong, not like something is broken. That’s all it is. Wrongness. He grits his teeth and breathes intently through his nose.

It’s not much longer before the technician calls the end of the third liter. The Soldier’s guts certainly feel like they’re near the breaking point. At some point warm water forced its way past a valve inside him and started spilling into his small intestine, which takes some pressure off the large but feels even worse. He’s sweating in earnest now. He glances to the side where the rest of that equipment stands, cold with dread at the thought of another liter.

The second technician says, “That’s our mark. He needs to hold it for at least thirty.”

“Surely he can fit another liter,” the first says, already reaching for it. The Soldier whimpers in distress.

“That’s enough,” the fourth technician cuts in again. “We have the numbers we need. If you really want to test maximum capacity, submit it to management as usual.”

The first rolls his eyes but says, “Very well,” and then addresses the Soldier, rubbing his tender belly again as he removes the nozzle. “Soldier. You heard Dr. Yahontov. You need to retain for at least thirty minutes. Do not let a drop escape you. These are your orders.”

“Understood,” he grunts, and half an hour of Hell begins with the click of a stopwatch.

It’s solidly awful. He can’t really move his limbs to seek a more comfortable position. The table is cold against his back, and his soft parts are on full display, exposed and vulnerable. Vulnerability does not suit him, he decides. But his vulnerability belongs to Hydra, as does his body, and he has his orders, so he endures. He does not fucking like it but he endures.

When the time is over, the technicians clear a path in front of him and order him to expel the water. That’s almost as awful and painful as getting filled up with, but each agonizing push brings a little more relief to the pressure that’s had him ready to crawl out of his skin. The drains in the floor and rubber boots on the technicians make sense now. It’s an awful lot of water. At least there’s no foul smell involved; it makes sense that his guts would be empty coming out of the ice.

At certain points they unhook his heels from the stirrups to turn him this way and that, letting gravity move the water around his innards so that he can force it back out. It’s a long and terrible process, but at least he can breathe easier now. The intestine is designed to move things out, not in, so at least biology is on his side this time.

One of the techs hoses the floor down and then cleans the Soldier and table. The first changes into new disposable gloves and rearranges the Soldier back into position with his feet in the stirrups.

“You’ve passed the first test,” the technician tells him. “You’ll like the second. Just lie back and relax.”

The man pumps lube onto his gloved fingers and applies them to the Soldier’s anus again. The cold gel is a bit of a shock, but after spending all that time spread open on the nozzle, he takes two fingers right away without any notable discomfort. He sighs and tries to relax as he was told; his belly is still sore, but a nice slicked-up fingerfuck feels divine by comparison. He knows his pleasure is nothing but an offhand curiosity to these people but all the same he’s grateful to them that they allow him to have it, instead of punishing him for his physical reaction.

It’s over all too soon. “Commencing speculum, beginning at two centimeters.” The first technician picks up the weird device from the tray, lubes one end, and puts it where his fingers just were. The metal is as cold as it is slick, which is less pleasant.

It holds him open: two prongs catch his rim and force it to spread apart. The Soldier takes this quietly. He listens as the technician narrates increasing the spread in slow increments, each new one followed by a fresh manual lubing of his anus and a few minutes for the ring to adjust.

When they reach four centimeters, the technician says, “Commencing first probe, four centimeters,” and reaches for one of the things that look like silver bullets. He lubes it, too, and slides it through the arms of the speculum into the Soldier’s warm guts.

The Soldier tries very, very hard not to make a sound, but he’s breathing with his mouth open at this point. The speculum gets removed and he’s outright fucked with the probe. It feels _wonderful_ right up to the point when it meets resistance a few inches inside him, and then it’s a lot less fun. But the technician slides it deeper still, gently but firmly forcing something inside the Soldier to open up for the probe the same way his asshole has opened for him.

“Rectosigmoid juncture breached. Note arousal negated. Soldier, any damage to report?”

The Soldier makes a face and considers reporting how not-fun that felt. It’s fine now, though, so he decides it’s not important. He shakes his head.

“Good.” And he gets fucked a while more, long enough for his flagging erection to start waking back up again.

Once the Soldier is squirming and panting, the probe gets taken away, to his frustration. The technician holds his asshole open with two fingers to fit the speculum back in, and they begin another round of stretching. They go up to five centimeters, five and a half, six. With each whole number there’s a pause to use a new, wider probe. The Soldier’s arousal grows and grows throughout those ministrations, but never crests—it’s noted dispassionately and otherwise ignored, just like his red-faced frustration at having the probes removed too soon for him to get anywhere.

It feels like this goes on for hours. He’s sweaty and breathing hard all over again, drooling from the cock and biting his lip when the technician announces seven centimeters and slides the largest, heaviest probe yet deep into his guts. It’s big enough to press against that electric spot inside him non-stop and this just might break him if they don’t let him crest that fucking ledge he keeps toeing up against, god his cock is so hard it hurts—

“That’s our target,” the second technician cuts in. The Soldier thinks a few words he would never dream of daring to speak. Instead he growls out his frustration and thunks his head back again. A moment later he grits his teeth around a squeal because the first technician _seizes his cock_ and _squeezes_ —once.

“Poor thing, you almost made it, didn’t you,” the technician says, his voice lackadaisical. “I’m sure you’ll get there with our friend. Radio the major. I’ll scent him and then he’s ready.”

Someone hands the first technician a jar and a syringe, sans needle. He draws a thick off-yellow liquid, pokes it up into the Soldier’s ass, and injects it into him. From what the Soldier can smell of it, it’s musky and heavy, like heated metal and piles of worn leather.

With that, the Soldier is unstrapped from the table and lead on shaky legs down another series of hallways, into the unknown—and, doubtless, his next torment.

* * *

Blast doors open onto a large room ( _a ballroom?_ something in him wonders) and the guards shove him in with the butts of their rifles. The walls are tall, two stories at least; halfway up in a ring all around the room are jutting bars strung with razor wire, humming with electricity. Above that is a long panel of floor-to-ceiling windows: an observation deck. He spots Major Brasiliev looking down on his lone, naked form. The segments of his metal arm shift uneasily.

He paces the room slowly, growing more and more ill-at-ease with every detail he takes in. The room smells of disinfectant, musk, and old gore. There are gouges here and there in the walls and floor, grouped in fours and fives, like...like claw marks. What could leave claw marks in solid cement? He flexes a metal fist. The arm could, but the spread is much bigger than a human hand (and while he is not a person, he is certainly person-sized and person-shaped).

Some of the gouges have spots of red ground into them. Blood that wasn’t successfully washed off. Is it human blood, or that of whatever monstrosity left those marks? His body coils into a thrumming-tense spring, ready to lash out at the slightest threat. What he wouldn’t give for the comfortable weights of a gun in his hands and knives at his waist and thighs.

Several spots along the razor wire have tiny scraps of flesh and off-white hair caught in them. His skin crawls.

The Soldier paces back to his starting point, now that he’s a bundle of nerves, and looks up at the observation deck. “What is my mission?” he calls.

Major Brasiliev moves over to a control panel, presumably where a microphone stands. His voice comes out over a PA speaker. “This is a breeding mission, Soldier. You have already shown me that you know what to do. So simply do it again.”

He puts together the room, the tests, and the mission, and suddenly feels sick to his stomach. Breeding...to _what?_

A wall begins to part—hidden blast doors opening—and he steels himself for the answer.

A deep rumble issues from the darkened hall beyond those doors. A bear maybe? Would they really expect him to breed with a goddamn bear?

The thing that comes slithering out of the doorway is no goddamn bear.

In fact he has no fucking clue _what_ it is. He can’t explain the whole of it, only take in parts. It’s bigger than a horse: covered in shaggy fur dappled in greys and bluish white; it moves like a lizard, with its thick limbs splayed out to the side. Its head is wide and wedge-shaped like a fox gone wrong, bearing a broad, fang-filled mouth that tapers to a point and opens eagerly when the beast spots him with silver, slit-pupiled eyes. Its ears, held erect, are tall and triangular like those of a lynx; its claws are enormous and lustrous like metal; its tail and neck are both long, muscular, and thick.

He’s grateful his bladder is empty because it’s coming towards him, scenting the air both with its catlike snout and a pointed, varanine tongue.

And then the very strangest sensation since he woke up: something pushing against his mind as if trying to make room for itself in his skull. He staggers back, shaking his head a little, but with no defense against this bizarre assault, that force breaks through, and with it a deep, velvety voice.

 _They brought me another,_ the voice purrs. _Which are you, little one: mate or meat?_

It’s not Russian but he understands it all the same. It’s not _language_ at all, not as he knows it: meaning without words.

The Soldier looks around wildly. It’s just the beast and himself in the room, and the beast is watching him with an air of expectation, tail waving in slow, sinuous curves. He wildly does not want to be meat.

“Mate,” he says, then, feeling a little like he’s lost his mind talking to this impossible thing.

The beast presses closer, sniffing him. _You smell ready. The solstice is here. I smell your heat. Are you more suitable than the others?_

“What others?” the Soldier asks warily. He takes a cautious step back. His heat? It smells his…. The thick substance he had squirted into him. They must have dosed him with pheromones to make him smell...receptive.

_The ones they sent before you. They screamed and tore and fought and bled. It seems I was too much for them. Will I be too much for you?_

He swallows thickly. It was probably too much to hope for at this point that the beast would turn out to be female. Those tests they ran on him before would be pointless then. Pointless torment isn’t out of the question, something assures him, but the same voice tells him that when it comes to breeding, he is there not for fucking but to be fucked.

He sure feels fucked right now.

So he shores up his courage, reminds himself of his mission, and says, “Only one way to find out.”

 _I like you. Braver than the rest,_ the beast’s telepathic voice croons at him. _Kneel for me, human. Down on the ground. Yes, like that._

Not bothering to correct him that he’s not really human, the Soldier shivers on his hands and knees as the beast circles him, scents him, licks him. Its breath smells like honey and old meat. A twinge of curiosity flares at that, and he latches onto it desperately. “What are you?”

The creature pauses, clearly not expecting the question. _I am that which I am. I am one of very few left. I am the one who lurks beneath snowdrifts. I am a prisoner, but men cannot hold me forever._

“Lurker,” the Soldier breathes, staring at the floor; it’s the Russian word for a spy or a scout, but it’s the closest he can think of. He's not even sure why he says it. Maybe his brain is just having trouble processing so much intent without translating it into words.

The monster blinks at him slowly. _Ah yes, the curse of Adam: your people must name things. Is that what you would call me?_

He doesn't know what the hell the curse of Adam is, but instinct tells him he is allowed a limited capacity at making decisions on a mission; so the Soldier hesitates, then nods.

 _So be it. You’re stalling. Afraid. If you are as ready for me as you smell, and if you do not fight me, you will live to bear my young._

Male for certain, then. He tries not to think about how big Lurker’s dick must be. He’ll find out soon enough. The Soldier opts not to disillusion Lurker about their chances of successfully creating young.

“I’m ready,” he sighs. He’s still trembling when Lurker comes up behind him and covers him with his great shaggy body, resting his hot belly against the Soldier’s back.

 _Relax,_ Lurker tells him. _Climax for me if you can, as often as you can. All the better chance that you catch._

It proves a little hard to relax when some sort of short-furred, fleshy tendrils snake around his upper thighs and hoist him up into position. That short-circuits his brain bad enough that the touch of a hot, wet cock-head against his rump almost doesn’t register until it’s too late. The tendrils are surprisingly strong for as thin as they are, two fingers wide he’d guess: they curl and push to hold him relatively still while Lurker’s hips start pumping.

And yes, it’s one hell of a big cock. Hard, thick, and damp, it slides across his lower back, between his thighs, and jabs him terribly in one asscheek. This creature has a tiny target and awful aim.

“Stop, wait, let me help,” the Soldier grunts. Lurker growls out loud but pauses. The Soldier plants his shoulder on the ground and reaches back as far as he can between his legs until he finds the spongy, teardrop-shaped head of Lurker’s cock. The beast’s surprised, pleased rumble vibrates against the Soldier’s back. He guides the pointed tip to his hole, still slick from his tests, and pushes back until it begins to breach him.

 _So clever!_ Lurker’s mental voice gasps. His hips jut forward and far too many inches of fist-thick cock surge up the Soldier’s defenseless ass. The Soldier yelps, but Lurker has him now, and seems to know exactly what to do with him. In three great thrusts that knock the wind right out of the Soldier’s lungs, Lurker shoves his dick deep inside until the Soldier’s sure there’s no room for any more. That penis is as thick as the biggest probe that was used on him before, and long, and impossibly hot. All rational thought flees his mind, leaving only the astonishment and all-consuming sensation of the size and heat of that monstrous cock. When it starts fucking him in earnest it’s equal parts painful, terrifying...and arousing.

It’s a good fucking thing that both Lurker’s cock and the Soldier’s rectum were slick to begin with: there’s little in the way of friction inside him, just smooth, wet thrusts that make rhythmic slurping noises echo through the oversized room. The Soldier’s groans hitch where the beast thrusts into him; he does his best to relax into his groin-tendrils’ grasp that holds him up and in place as surely as a pair of hands. He puts his flesh hand on his lower belly, and gasps—he can feel Lurker’s massive cock sliding up his ass _from the outside_.

All the while, Lurker’s mental voice babbles things like _Yes, yes_ and _Tight_ and _Take it_ as the Soldier’s fucked within an inch of his life. The praise is as shocking as his thrusts. The beast’s honeyed words of pleasure vibrate through the Soldier’s skull and stiffen up his cock as surely as the implacable pressure against that electric spot inside him.

 _It feels good, doesn’t it, little one,_ Lurker purrs into him, rumbling in pleasure both physically and telepathically. _You are the one. You will take my knot and I’ll seed you well, and by the next solstice you’ll whelp a strong litter!_

The Soldier tries to speak, chokes on his words when a series of rapid thrusts makes his body shake like a ragdoll, and tries again. “I’ll—I’ll take your what?”

_You’ll find out soon, my mate. Climax for me now. I need you relaxed to put it in you._

He cries out again and reaches between his legs to grasp his bouncing cock. All he has to do is hold his fist still and the beast’s powerful thrusts make him jerk back and forth in his own grip. He squeezes—carefully, because it’s the cool, steel-crushing metal of his left hand—and soon his body seizes up in orgasm, and he wails through it with hot fur sliding back and forth across his skin.

 _Good boy,_ Lurker purrs, and the Soldier chokes again. Fuck, fuck fuck, if he doesn’t think he’ll get a litter out of the Soldier, he’ll—

 _Of course I know you’re male. I can usually tell the difference. Your males and females are different enough they sometimes look like different species. Be calm, my mate. I know you won’t really get pregnant._ Lurker curls his head down to lick the Soldier’s sweaty neck, and the Soldier reaches up again to sink his fingers into thick, wooly fur. _But it’s the solstice, and I need this, and it is nice to pretend. Just like covering a decoy-male. Now...relax._

He tries to. Lurker’s tendrils hold him tight, and Lurker’s hips push hard against the globes of his ass, and with both of them growling and straining, an even thicker stretch of cock the Soldier hadn’t realized was _there_ pops inside.

“What was _that,_ ” he gasps.

 _My knot. It will keep us together when I climax. You’ll see._ Lurker reaches down with a terrifying paw tipped in gleaming scythes and... _pets_ him, and keeps thrusting. A thrill of fear shivers through the Soldier for those claws oh-so-gently scraping across his bare skin. It makes him tense around the cock spearing him open, and that makes him gasp and cry out, overwhelmed all over again. No, no, he's supposed to relax, so he fights every instinct and tries harder to force his body to loosen up.

With some difficulty, Lurker pops the thicker “ball” of rock-hard flesh back out...then back in again...out...and back in...with the Soldier wailing and crying out all the while as his asshole gets absolutely ruined. Eventually his hole stops fighting, stretched out enough to allow easier passage to something wider than his palm, and the beast gets back to fucking him as relentlessly as before. The Soldier looks down and watches each thrust deform his stomach, making his flat belly bulge.

Once the pain of the stretch subsides, the Soldier discovers something about that knot: when it pops inside, it rolls right across that good spot with crushing force, filling him up with so much staticky pleasure he’s shocked he hasn’t come yet. He doesn’t have long to wait before he crests that very hill, punching through a velvet barrier into scintillating pleasure, and Lurker praises him again for it while he’s still rubber-boned and reeling.

He likes Lurker a lot more than Major Brasiliev. This is the best mission ever.

A few breathless minutes of wet, hot fucking later, he rethinks his position. _Here it comes,_ Lurker growls in between his ears, and he thrusts in deep, deep enough to pop his knot in, deep enough it hurts, so deep there’s no gut left in that direction, and the beast begins to come in great, fiery gouts. But at the same moment, the knot gets even thicker than it had been already—it inflates to a ridiculous, terrifying size, so big the Soldier _screams—_ he’s going to be torn apart inside!

“It’s too big, you’re gonna rip me open,” he wails, squirming against the tendrils’ clutch.

 _Do you really think that’s a good idea, little one?_ To prove his point, Lurker pulls his cock back. The Soldier sees his point immediately.

“Leave it in, leave it in! Fuck….” His breath hitches. It’s too much. It’s like having an arm shoved up his ass _plus_ a fist in his rectum. The knot is stuck within his pelvic girdle with no hope of coming out without grievous hurt. It’s not just sitting there inside, him, either; the whole thing jerks every few seconds with a new shot of come. Lurker rolls his hips lazily, growling in pleasure as he fills the Soldier up, seemingly immune to the Soldier's distress.

_Not to worry, my mate, you’ll soon be pregnant with my kits...and that’s how I’ll keep you stuffed to the brim with me. Next solstice, as soon as you give birth, our captors will bring you to me again and we’ll repeat this, on and on until we make our escape._

That brings the Soldier to stillness. There is no escape from Hydra. It’s unthinkable. Lurker licks him, and he absently pets his silky snout. “I can’t escape them,” he whispers. Maybe if he’s lucky, Major Brasiliev won’t hear.

_I can. Be mine, and I will take you with me._

He kneels there in silence and tries to imagine it. No sooner does he envision fleeing into the snow with Lurker by his side than a lance of pain sears his brain—there and gone again. On instinct he knows: that was Hydra, punishing him for daring to even think about escape. They will find him if he runs. When they find him, they will punish him, and it will hurt in ways he can’t imagine. They will recapture Lurker and hurt him too. “I can’t,” he wheezes, “I can’t, I can’t.”

 _Very well. I will miss you when I am free, and we will make this one count._ _Lie with me, we’ll be like this a while._

Lurker and the Soldier begin the awkward task of lying down on their sides. It’s demonstrably worse for the Soldier, skewered as he is on half a meter of penis, but they make it. It’s a reprieve for his knees, for certain. So he just lies there, groaning, while a telepathic taiga monster pumps him full of a seemingly endless supply of come.

Soon he understands what the first test had been about. As Lurker keeps ejaculating into him, his guts fill with so much semen he starts to feel bloated. Panting, he rubs his stomach to try to soothe it. If he holds his hand on the right spot he can feel Lurker’s swollen cock-head where it’s buried deep in his colon, jumping as it spurts.

“How long are we going to be stuck here?” he asks quietly.

Lurker considers. _Longer than it takes to eat a rabbit, less time than it takes to eat a deer._

The Soldier blinks. He should have known better than to ask.

Time passes. His guts grow fuller and fuller. It begins to hurt—sharp little knives in his belly, a needlepoint pain. He whimpers here and there but tries not to squirm, lest he upset the giant monster still fucking him. Now and then Lurker curls down to lick him, or stuffs nice words into his head. He lies back against the wall of flesh and fur at his back and focuses on regulating his breath. He tries to focus on the coarse but plush fur pressed to his back and legs. For a snow monster, Lurker is very warm. If it weren’t for being knotted and overstuffed with come he might be very comfortable there.

He finally gets a look at the tendrils, too. They are in fact furred tentacles coiled around his thighs; they stem from Lurker’s groin, growing out from either side of his cock. He reaches down to stroke one. Truth be told he’s fairly grateful for them right now, because they keep his hips from moving away in a way that might hurt him worse than three liters of semen could.

“You use these for sex?” He’s not sure what it is about Lurker that loosens his tongue. Maybe just the fact that he isn’t Hydra. Still, he should be more careful, because his masters _are_ listening.

 _Yes. Exactly like this. My people are fierce. Sometimes we fight even when we_ want _to be mounted. These are much stronger than what you feel now. If you fought me, you would see how tight they can hold._

The Soldier shakes his head. “I believe you. I don’t fight it even when I _don’t_ want to be mounted. It’s my place to be bred.”

 _You should have more pride,_ Lurker sends him with a snort.

“Humans have pride. I have what Hydra decides I must have,” he shrugs, wincing in discomfort.

Lurker’s great shaggy head tilts down at him. _You seem human to me._

The Soldier isn’t sure what to say to that. “They made me that way.” A pause, mostly to catch his breath. “I don’t mind when they fuck me. Sometimes it’s good.”

_If you change your mind, you are still welcome to escape with me._

He shakes his head again. “Thank you but no. That is not an option for me.”

They slip into silence, save for the Soldier’s small sighs and hisses of bloated, cramping pain. He watches his belly become visibly swollen again in slow motion. It’s not as disturbing a sight this time, now that he’s prepared for it, but it’s still unsettling.

Lurker seems to take a different view of it. He reaches down to delicately rub the Soldier’s poor stomach where it’s popped out from its normal flatness. _A swollen belly suits you. I would keep you very full. Fresh meat and my cock._ Lurker sighs. _No, little one, don’t say it, I know. Not much longer now._

The monster lays his head down pillowed on his forelegs, and the Soldier does the same on the crook of an arm. A few minutes later the all-consuming pressure in his rectum eases rather suddenly, and the immense cock that must have been trapped inside him for half an hour at least starts to slip out of his ass with a gurgling rush of hot semen. It cascades down his ass and groin, and he groans, tenses, and comes hard—he’d barely noticed he was hard so it catches him off-guard. Thinking back to his tests, he shifts position a few times trying to empty out the contents causing his stomach so much distress. It’s messy and kind of awful, just as it was the first time around, only this time there’s the added element of tackiness in the come sticking to his skin. Altogether not a fun experience, but fun is not a factor the Soldier expects out of life.

Lurker sweeps the Soldier up against his chest, between the shaggy trunks of his forelegs, and curls around him. _Well done, little mate. Rest now. You will need your strength back before we do this again._

The Soldier jolts. “What do you mean, again?”

The monster huffs, peering at him with one great silver eye. _The solstice and your heat are not over yet. We will mate until they are. This is what you were given to me for._

Swallowing hard, the Soldier reminds himself of his mission—and, now that he thinks of it, the indefinite nature of its duration. He tries to doze, but never quite makes it to sleep, even while Lurker falls into slumber around him.

* * *

They rouse after about an hour’s rest and Lurker immediately begins nuzzling and snorting across the Soldier’s skin. Lying flat on his back, he swings his hips up in offering, ready to be used again. This time he gets to see the tendrils on either side of the cock-sheath descend to coil around his thighs. They pull him up higher, spread him wider, readying him for the huge wet cock slipping out into view.

It’s alluring in an alien way. Lurker’s cock is a rosy pink flushing deep red at the head. The end is thick, tapering down towards the base where it blooms back out into the knot. It doesn’t look quite so imposing right now, but he knows that once it’s inside him it will get bigger—both longer and thicker still.

He reaches down to stroke the smooth, slick head with his flesh hand before guiding it to his hole. Even though he’s still a little sore from their first round, the size is easier to take this time. In no time Lurker has fed and humped his long, thick cock into the vulnerable human body trapped beneath him, and he fucks the Soldier within an inch of his life all over again.

The knot is still hard to take. At least he knows what to expect this time. He grits his teeth and pushes his hips up into it, welcoming it into his body, if not without difficulty. He’s got a hand around his own shaft letting the force of Lurker’s thrusts fuck himself into his fist. With a reedy groan he shakes his way through letting the knot plunge all the way inside, and as it rolls across that good spot with crushing, thunderous pressure he comes hard enough to splash his chin with spunk. There is no respite with Lurker inside him, no moment of pause where he isn’t overwhelmed by the size and strength of the monster’s rutting meat, no hollow in his body not filled with cock or breath. He understands, straining and screaming beneath the monster’s belly, that Hydra must have made him for this: not just for stalking and for killing, but as a vessel for another’s pleasure, a hole for a cock to make a home in, and he is content in his mission.

A sort of peace fills him, and so does the monster’s sperm. His guts strain against the volume, and it hurts, and tears prick his eyes, but knowing he was made for this makes the suffering easier.

 _Perfect,_ Lurker speaks into his mind. The words roll over him like nails down his back. It’s only right, isn’t it, that the beast thrust himself into the Soldier’s thoughts the same way he penetrates the Soldier’s ass: an irresistible force, an implacable and alien presence.

Pain be damned, he comes again, and once more with a yelp when Lurker tries to tug his knot out too soon, and he whimpers through dry orgasm when that giant cock finally does start to slide out of the depths of him. He’s filthy and exhausted. This time, when Lurker pulls him close, he does lose consciousness for a while.

And so they go on together: they fuck for an hour with the Soldier on his back or on his knees or against the wall or held like a toy in Lurker’s claws as the monster reclines on his back, both of them growling and gasping, clutching their mismatched bodies tight—and only when the Soldier is filled to bursting with monster come and Lurker has had his fill of quivering human flesh do they collapse into a sticky, panting pile and sleep an hour more.

 _I could keep you,_ Lurker tells him at some point. _I could do their bidding with you as the price for my loyalty._

The Soldier mulls this over. He knows he is Hydra’s most prized weapon, a tool but an important one. “I don’t think they’d give me up,” he says honestly.

Lurker growls, and the Soldier feels the rumble through his entire body. _Not forever. Remember, Shining Arm, I’ve told you. They cannot hold me for long. But they want me to kill for them, and up till now they’ve offered nothing enticing to me. But you. I could fuck you every night for a hundred years and not tire of your cunt._

A weird warmth fuzzes up the Soldier’s chest. He doesn’t have a name for it, so he pays it no mind. Such negotiations are no concern of his, one way or another; so he sighs, and grinds his hips in a little circle around the knot as it presses for entry, and loses himself in hours upon hours of this sweet unholy union.

* * *

A long time later, as they fuck, the knot doesn’t inflate, and Lurker seems a little frustrated by it until the moment he seems to realize something with a flat _Ah._

“What’s wrong,” the Soldier pants, “I’m ready, I’m ready, knot me.”

 _I can’t. The solstice has passed._ But his tendrils grip the Soldier’s thighs tighter. _I’ve bred you for the last time this season, it seems, but I can finish fucking you all the same._

And he does with gusto and force. This time, instead of filling the Soldier to the very limits of his guts, Lurker’s orgasm gushes up inside him for less than a minute before he’s spent. The Soldier’s not sure if he’s disappointed or relieved.

The tendrils ease the Soldier back down to the—frankly disgusting, sticky floor, and Lurker’s softening cock slides out of his aching guts one last time. The Soldier lies there in a puddle of cooling monster come, Lurker stands above him, and the two of them catch their breath.

 _You were a fine prize, little mate,_ Lurker purrs into his mind with fondness suffusing the message. _I hope to taste you again another time._

The monster gently licks the Soldier’s face, and the Soldier pets the silky fur of the monster’s snout. Finally satisfied, Lurker points his nose up at the observation deck—god, the Soldier had damn near forgotten Major Brasiliev watching from above!—and lets out a short but bone-shaking roar.

Whatever telepathic message Lurker sent to the man, a moment later blast doors open back into the dark, and silently the monster pads off into the shadows.

It’s a few minutes yet until the other set of blast doors open and guards retrieve the Soldier himself. He’s barely present as they lead him around and hose him down, and he’s unbothered when all four guards take turns using him once he’s clean. He pays no attention to their jeers about the looseness of his hole and his passive compliance with their rape. This was not within his mission parameters, but he has a new understanding of what Hydra means his body for, so he lets them have their fun. It’s nice to have their greedy hands all over his skin anyway, and over the past day and night he’s proven how well-suited he is to taking cock.

They must be done with him now, because they lead him to the cryo chamber afterward. A pang of… _something_ stabs the Soldier’s chest, some sort of loss he doesn’t understand.

The cold takes him, and then the dark.

* * *

The next time he meets the one who lurks beneath snowdrifts, he has no memory of the beast, nor any clue what he means when he tells the Soldier he and Hydra made a deal. He has no memory of the monster, and must learn his place beneath him all over again.


	2. Terms of Engagement

**Summary for the Chapter:**

> Bucky Barnes is having a bad day. In the scope of his life, that’s really saying something. But hey, at least he gets to kill Nazis.

Everything about this fucking mission has been a mess. Someone along the chain got shitty intel: what was supposed to be a retrieval mission went sideways when it turned out the so-called “abandoned” Hydra base...wasn’t.

It was very goddamn active, and Bucky was very goddamn done.

Too many of the SHIELD agents that came with them are pencil necks with the self-preservation instinct of a flan. They lost a few in the initial ambush before Steve, Bucky, Sam, and Nat pushed the squid Nazis back and led the SHIELD guys who knew what the fuck they were doing onto the offensive. It hasn’t stopped being a gong show for a moment since then.

The place is all blind corners and booby traps. The big problem Bucky’s keeping to his goddamn self is some of the booby traps are metaphorical, because they exist in his head, and when _they_ go off he can’t tell the past from present for a couple minutes. He’s pretty sure the others are starting to get suspicious (Steve, damn him, knows his tells) so _that_ situation is a ticking bomb to boot.

And then there’s— Here’s the thing. Bucky Barnes would really prefer not to kill anyone. But depending on who it is, Bucky Barnes sure as hell does enjoy killing. He’s been really fucking good at it ever since the War, and he’s only gotten better at it since, but it’s a _thrill_ that he frankly wishes didn’t do it for him like it does. But in his defense, it’s really only one group of people he really likes to kill, and that’s _fucking Nazis_.

And that goes double for Hydra.

So while any other mission would be a bunch of arm-breaking and non-fatal gunshots and pulled punches, he gets one look at that gleam of righteous hate in the blue of Steve’s eyes and he knows it is time to unleash the fucking beast on these sonsabitches.

He tries to keep this secret too, but even though he’s recovered enough to go on active duty with the Avengers, the Winter Soldier never _really_ went away. He sleeps in Bucky’s limbic system, coiled beneath his ego like a snake hiding in the roots of a tree—and part of the pact that keeps him dormant is knowing when and how to wake him up.

When Hydra had him brainwashed he’d never realized how fucking angry he was all the time. Now the Soldier feeds on Bucky’s hatred and sharpens his every edge to razors. He’s a predator, he’s a battering ram, he’s a bunker buster brought to a knife fight. 

All of this is to say: he’s slaughtering them like lambs, and he’s _enjoying_ it.

But the mission is still a mess. It was _supposed_ to be a quiet expedition, but _no_. It doesn’t matter, he thinks savagely as he pulverizes a man’s neck in his metal fist; once they’ve hunted down and killed every last squiddie in the compound, it’ll be a quiet expedition after all. Just with a few less scientists. Goddammit.

One of these weird curved hallways converges with another and he catches up with Sam, who’s got a split lip and the start of a nasty goose egg at his temple. “You look like shit,” Bucky informs him.

“Fuck you too, you should see the other guy,” Sam says without heat. “We’re still pushing south, right? Which goddamn way is south?”

Bucky takes a second to fight tooth and nail against another flashback trying to sneak up on him. The last few have made his stomach hurt like hell. He blinks it off and nods down the way he was going. “This way.”

And then it hits him. Fuck only knows what _it_ is, but it hits him like a ton of bricks. It’s a wave of wrenching nausea and a headache so intense it literally blinds him for a moment. Bucky cries out and stumbles sideways, metal arm crunching through the plaster on the wall.

He’s about to ask what the _hell_ that was when he hears it, like thunder following lightning: a bone-shaking _roar_ , a sound like a tiger ate a tornado.

Something in him knows that sound.

“What the _fuck,_ ” Sam saves him the trouble of yelling. When Bucky looks over he finds Sam half-collapsed against the other wall too and holding his head. He seeks Bucky’s gaze and holds it. “What. Was _that._ ”

There’s a word on the tip of Bucky’s tongue. He can taste its shape but it’s only half-formed. He shakes his head. “Familiar. I don’t know.”

“Barnes. Remind me. What was Hydra researching here back in the day?”

Bucky scrapes his tongue against the edges of his teeth and pushes off the wall. His rational mind is screaming to book it in the opposite direction from that sound, but he’s woken up the Winter Soldier for this, and the Soldier doesn’t stop for things like fear.

“Nothing,” he tells Sam as he starts off down the hall again. “It was a gulag.”

They make their way through deliberately confusing corridors, bursting into side rooms and occasionally tearing Hydra goons apart along the way. The familiarity of the place is really getting on Bucky’s nerves considering none of that familiarity seems to help him find his fucking way around. They hit more than one dead end, and Bucky puts his fist through more than one wall over it. But eventually they make it to a courtyard—or what looks like one at first, but it’s really just a large, tall room where most of the roof has collapsed and Hydra just decided to fucking leave it that way, because, he doesn’t fucking know, The Aesthetic or something. There’s a ring of razor wire strung around the walls about halfway up. That’s annoyingly familiar, too, but who fuckin’ knows what that’s about.

It’s the site of a firefight in progress. SHIELD plus Nat on one side, Hydra spread out on the other, all of them using rubble and overturned furniture for cover. Bucky signals to Sam and instinctively seeks cover of his own so he can start picking off squiddies that stick their stupid heads up. Behind the Hydra goons are a pair of blast doors that have been chained shut and heavily barricaded from this side. _That’s_ curious.

Sam and Bucky both crack off a few shots, but the place is messy enough that it’s almost impossible to get a clear sightline. He’s gonna have to pull a Steve on this one. He takes a few quick, growling breaths to psych himself up for the charge when—

_BOOM._

The barricaded blast doors shake like a grenade just went off on the other side of them, sending Hydra agents scattering. An instant later, a chorus of pained screams echoes across the ruined room. Bucky’s voice is among them as that mysterious force slams into him again, the nausea and instant migraine. The roar follows another half-second afterward, and it’s a whole lot louder this time.

”Sounds like our cue to leave,” Nat calls, already pulling back.

_BOOM._

The doors shake again. Dust and debris rain down from above. The squiddies are in a panic now, risking breaking cover to dash for the exits, and the SHIELD side is in barely-controlled disarray. Bucky catches something along the lines of _It’s awake_ in all the yelling. He doesn’t have long to wonder what the fuck that means before he gets his answer.

_BOOM._

The concussion of the blast doors crashing open sends a great thick plume of dust rushing into the room, swirling around the shrapnel of the planks and cinderblock and other things that had just a moment ago been desperately piled against it. The end of that sound blends with the beginning of another roar and suddenly there’s a shape the size of a fucking polar bear rushing, crashing through, and there’s screaming, and the sick ripping sounds of flesh and bone being rent apart, and gunfire lighting up the grey-brown cloud still filling the room.

The SHIELD agents are shouting now too—most falling back, a brave few pushing forward to fire half-blind into the murk.

“What the shit, what the _hell is that,_ ” Sam yells beside Bucky, grabbing at the straps of his leather tac jacket and trying to pull him backwards. But Bucky—

He’s transfixed. He knows this. He _knows_ this. He catches sight of a long, white, lizard-like tail whipping through the dust. The thing from beyond the barricade whips around, and the body of a Hydra agent with his head crushed to pulp goes flying across the faux courtyard to crash against a broken table on the SHIELD side...or at least the top half of the body, anyway.

Bucky casts around quickly for Nat and spares a heartbeat’s worth of relief that she’s gotten the fuck out of dodge. Too many SHIELD agents are still shooting at the thing, though. One last scream on the Hydra side ends in a horrible, choked-off gurgle and a splattering sound...and the thing wheels around to its next targets.

Out of the dust cloud emerges a creature that looks like a combination of fox, lynx, and monitor lizard covered in shaggy off-white fur dappled in shadow blue. Its broad face, long neck, pointed snout, and gleaming claws are all stained bright red and dripping with fresh human gore; its dagger-like fangs are bared, and its silver eyes gleam with hate.

The SHIELD agents keep firing, but the bullets never reach its hide: they hover an arm’s length away in midair, impossibly suspended by some invisible force.

Bucky can’t breathe. A word takes shape on his tongue and he screams it out as the monster lunges at his allies:

“LAZUTCHIK!”

The monster lurches to a stop and swings its great grizzled head around to stare straight at Bucky, widening silver eyes boring into his and rooting his feet to the spot.

For an instant there’s a sensation that defies description: a force, a burrowing, a demand, punching through the barrier of his consciousness like it was tissue. A voice like velvet over thorns washes over and through him—not language, but the logic behind language; not words, but the meaning behind words.

_Shining Arm. You are here._

“Lazutchik,” Bucky whispers. He takes a step towards the creature while the rest of his instincts scream at him to run the fuck away.

“Barnes we gotta get the fuck out of here,” Sam is yelling at him, pulling at his harness, “be a fucking weirdo later, let’s _go!_ ”

He shrugs the hand off. “No! No, it’s okay, I...I know him.” He takes a few more careful steps forward. “You know me.”

 _My little mate,_ the voice rumbles happily into his head, and it feels a bit like losing his mind. _I could never forget you, no matter how many times you forgot me._

“Stand down!” Bucky yells to the agents. “It’s...it’s okay, he’s a friend.”

_I am NOT their friend, Shining Arm. Stay where you are, I will kill the rest of them and then we will be free of this place!_

Bucky cusses. “No, no these guys, they’re not Hydra. Not Hydra! Just scared shitless. You don’t have to kill them, you’re free now.”

The monster—Lurker—wavers, looking for all the world like he’s not sure if he dares to hope that’s true. _I was before. They found me again and made me sleep. Stand aside, little mate, I will kill them first!_

“You gonna tell me what the fuck is going on? Are you _talking_ to that thing?” Sam yells.

A glance back tells Bucky that Sam has wisely backed up into the open doorway. He’s keeping his sidearms trained on Lurker, for all the fuckin’ good they’d do him.

Bucky nods. “He’s uh. He talks back.” He taps his forehead. “In here. He was Hydra’s prisoner too and right now I am _trying_ to convince him the rest of you _aren’t_ Hydra so if you would _please stay the fuck out of this._ ”

Sam raises his hands and backs up further into the doorway. He has a much lower threshold for Deeply Weird Shit than his supersoldier friends.

Bucky swallows thickly and swipes a hand over his face. If only he could remember more of— oh. Oh wait. Oh shit. _Now_ he remembers. And he knows what he has to do.

“Lazutchik, I’ll make you a deal,” he tells the creature.

For a terrifying moment, he loses the monster’s attention as he half-turns to snarl at the hunkered-down SHIELD agents...but then he twists his head back to look at Bucky again. _Make your offer._

It takes a couple tries to get the words out. “You remember what we did before, when I was given to you?” he finally manages. Lurker’s eyes gain a covetous glint. “We...we can do that again, if you let these people go. And a few others that came with me who aren’t in this room. Do we have a deal?”

Lurker pads closer, close enough to smell the blood and rent bowels on his breath. _It’s not the solstice._

Bucky takes a steadying breath. He doesn’t fully remember why, but that comes as a relief. But he does remember one particular thing at least. “You once told me you could do that for a hundred years, solstice or no. Lazutchik, do we have a deal?”

The monster considers, casting a glance back at the agents who haven’t wisely slipped away during the distraction. _We have a deal, Shining Arm. Ready yourself._

“Wait, uh, okay, just a—” Bucky backpedals as Lurker advances on him. “Not in front of them, okay? In...in private.”

_You are lucky I like you. Come._

Lurker turns and starts to slink off into the settling dust. Bucky takes another breath and looks back to Sam. “Do me a favor. Don’t follow me, no matter what you hear. I don’t want any of you seeing this.”

Sam, reasonably, stares at Bucky like he’s grown a second head, and yeah, that’s fair. “Just checking my understanding here, you just made some kind of deal with the giant psychic monster that killed about twenty men in two minutes and can stop fucking bullets, and you _don’t_ want backup.”

Well when he put it like _that_ it does sound batshit. Bucky presses his lips together and nods. “Yep, you got it right alright.”

“You are a crazy person. I can’t promise I can keep Steve from coming after your ass when he finds out about this. But whatever, man, if you say so, I’m _apparently_ gonna have to trust you here.”

Fuck, Steve. Bucky winces thinking of the tongue-lashing he’s going to get for this. But as long as he never, _ever_ finds out what Bucky’s deal entails, he can live with the torment of having Steve Rogers disappointed in him.

“Thanks, Sam. I’ll...catch up.”

And he trots to catch up with the great beast’s slithering gait as Lurker leads him out of sight.

* * *

Faint echoes of gunfire ring through the halls as Lurker leads Bucky deeper into the compound. They pass a number of dead Hydra agents violently torn apart. Nothing quite like the sight of disembodied limbs and spilled innards and the smells of blood and piss to get a guy in the mood. He just hopes Lurker doesn’t want to do the deed among his kills.

“There’s something important you should know,” Bucky tells the monster. “Back then...Hydra used these...tools to get me ready for you. That’s why it was easy to fuck me. But it’s been a long time since I’ve had sex.”

It’s not that he hasn’t had the urge or anything; just that there’s only really one person he’s had the urge to do it with, and the prospect of ruining his most important friendship with misplaced lust (let alone _queer_ lust) is terrifying.

 _Are you asking me to be gentle?_ Lurker sends him, sounding amused.

“Yes. Yeah. I can get myself ready but it’s not gonna be as easy as it was before.”

_So be it. But I remember your body, little mate. Eventually it will remember me too and let me have my way with it._

Bucky’s pulse picks up. The hallway curves, and curves again, and there in the middle of it Lurker stops and slithers around to face Bucky. _This will do. Take off your false skin for me and get ready._ Lurker puts his snout in the hollow of Bucky’s throat, sniffs him deeply, and licks his neck. 

A thrill runs up Bucky’s spine. He tilts his chin up and sinks his fingers into the fur beneath Lurker’s chin. This is really happening. His friends are somewhere else in the compound fighting his mortal enemy to the death, and he’s about to get laid for the first time since…since before the helicarriers. Three years now. He swallows a lump in his throat and starts stripping down.

Lurker hovers over him the whole time, growling quietly and nudging at him. The monster’s anticipation ripples across his mind. The concrete floor is bitter-cold against his skin when he lies down. Bucky spreads his shaking legs and runs a finger across the tight furl of his hole. What he wouldn’t give for some lube right now. He has to make do with spitting on his fingers, and that’s not going to last long.

The first breach is relatively easy; Bucky might not have been sexually active with anyone _else_ since he broke Hydra’s control, but that doesn’t mean he hasn’t taken the time to get intimately reacquainted with his prostate gland. None of the toys stashed under his bed are as big as he remembers the monster being, but at least they’ve kept his hole trained to accept penetration. Good fucking thing, that, since he’s about to put that training to the test in a big way.

One finger becomes two, and he scissors them apart as hard as he can stand, trying to force himself to stretch open. Lurker watches with the slits of his pupils dilated in interest, like a cat about to pounce. _I can’t wait to get back inside that hole,_ his voice purrs behind Bucky’s eyes. _Stretch it wide for me. I may not be able to knot you this time but you are going to take everything I have to give you._

Bucky whimpers, biting his lower lip. His cock clues in and starts stiffening up as it always does when he plays with his ass. Plunging those two fingers as deep inside as he can get them, he pulls on his sphincter, and reaches down to tease the tips of two more from his metal hand inside with them. The memory of having a speculum used on him bubbles up from the dark recesses of his mind and on the one hand, it’s horrifying that they did that to him—clearly what his therapist would call medical rape—but on the other hand, a speculum would be really fucking handy right now.

He needs to relax. This is just about the least-relaxing place and situation he’s ever been in. But he can do this. As much to distract himself from the situation as anything, he asks, “Why can’t you knot me?” while trying for a third finger on one hand.

_Simple: the knot is for mating, not fucking. It only forms for the solstice, when my people are in season. Any coupling we do the rest of the year is for fun or to avoid a fight. Mostly to avoid a fight. We are rare, and when we meet usually one or the other thing happens._

Bucky’s eyebrows rise. “That’s one way to settle a territory dispute I guess.” He grunts, trying to adjust his legs without losing his grip. “Human history would’a played out a lot differently if we did things that way.”

_That was what our captors used you for, was it not?_

Bucky scowls. “Guess so.”

And then Lurker comes in clutch with the ultimate distraction: he sets his claws on the insides of Bucky’s thighs to keep them spread apart, and starts lapping at his hole. Bucky groans, cock jumping against his belly. That tongue is large and wet and hot and a little rough, and it’s electric against such sensitive skin. That...that helps. It soothes the sting of the demanding stretch Bucky’s been imposing on himself, and he hums pleasantly with occasional gasps of the creature’s not-name.

As nice as that is, they don’t have all day. Bucky gives himself a few more minutes of tugging his hole open before rolling over onto his hands and knees. Lurker surges forward to cover him immediately. Thin furry tendrils snake around his thighs to hold his ass up, and the wet, spongy head of the monster’s steaming-hot cock pushes against his skin before he can do any more than squawk.

“Gently, gently,” Bucky reminds him desperately, “you gotta start slow.”

_Yes, yes. Guide me in, little mate._

Taking deep, steadying breaths, Bucky reaches back to grasp the cock head and puts it right up against his hole. Lurker pushes it into him with a little _pop_ of the ridge breaching him. Bucky cries out: it’s already an incredible stretch, and by the time the full, terrifying length is inside him it’s going to stretch him even wider. Lurker rumbles like a crocodile and oh-so-slowly forces more inside.

_You’re dry this time. Even more like fucking another male of my own kind. Not unpleasant._

“Don’t got any lube this time.” Bucky, for his part, is already sweating from the strain. The tip of Lurker’s cock reaches the first (technically last) bend in his colon and steadily forces it open. That hurts, and Bucky grits his teeth against the sensation, but once that juncture opens it’s a smooth, straight shot up his ass; the last foot or so penetrates him a lot easier. The tendrils tighten to hold him close to the base of Lurker’s cock, and it’s then that the monster starts to really fuck him.

It hurts. There’s no way around it. But he’s also hard as a rock and dribbling a non-stop stream of pre-cum, because yeah, it hurts, but it’s also _good_. It’s been so fucking long since anything has been this deep inside him, or filled him up so completely. It’s been a long time since he got prostate stimulation from anyone but himself. He’s missed this. He’s missed being touched, he’s missed _sex_ , and while this wasn’t exactly his first choice of how to break his dry spell, he will—and does—happily take it.

“God you’re so big,” he whimpers. Lurker might ruin him for human men. When he tries to picture himself doing this every day, though, he reconsiders. Then the monster picks up speed so their loins pop and smack against each other and he can’t fucking think of anything other than the giant cock ramming up his ass.

 _Climax for me,_ Lurker purrs, and Bucky barely has to squeeze his shaft before he’s coming like a train crash, screaming, shaking, blind with the pleasure of being so full of dick. Lurker doesn’t bother giving him a cooldown to recover, but goes right along happily plowing his asshole like a snowdrift in front of an ER. Bucky wails, overstimulated, _flying_ , high on endorphins, and Lurker answers his cries with tigrish growls.

It feels like it goes on for hours. Bucky thanks his lucky stars that the monster’s dick seems to be self-lubricating because the friction isn’t near as bad as he’d feared. There’s probably a lot of precome slicking up his insides. By a certain point Lurker has abandoned the pretense of taking him gently and starts fucking him into the ground. The tendrils around Bucky’s legs keep him from sliding away or falling down, and he’s glad for them too. He can’t really tell how long it’s been but he comes again—this time untouched, punched out of him by the monster cock breeding him relentlessly, and he screams and wails his way through that one too.

He’s just about to reach the crest of a third now. He’s begging Lurker “Please, please, please” but he’s not sure for what. The creature pushes Bucky’s chest down to the floor with a forepaw as it pounds him senseless. He can hardly draw a breath that doesn’t come out in a moan or yell. And finally, finally, Lurker thrusts in deep—right to the hilt where he’s thicker than a man’s fist—and bellows out a roar as he comes deep inside Bucky’s guts. Dully, he can feel the spurts, great hot gouts of semen gushing into him in shot after shot, and that’s what sends Bucky back over the edge as well. Lurker’s orgasm lasts far longer than his own; he’s already coming down and feeling overstimulated again and Lurker’s _still_ not done.

In a bright, hot flash he remembers his first time coupling with the beast: how it came inside him for so long they had to lie down together, how it swelled his guts until he damn near looked pregnant, how Lurker had cooed at him for catching a litter of his young. His dick gives a weak twitch but he decides he’s not going to examine that one today. He’s still sitting with this memory when it finally comes to an end: Lurker’s cock loses its stiffness and starts to slide out of him, which frankly feels exquisite, and his tentacles lower Bucky’s bottom half down so he can set his knees on the floor again. The now-soft cock head pulls free of his hole with another _pop_ and a gush of hot cum that spills down Bucky’s balls and thighs. He can feel cold air against the inside of his asshole where it gapes.

And because this mission is just the worst, that’s when he hears someone call out from behind them: “Bucky?!”

The cold of this place crashes into Bucky from all sides and he chokes. No. No, not now, not when he’s—

Lurker is already wheeling around with a thunderous snarl, ready to attack. Bucky twists and lunges for the nearer foreleg and shouts, “Lazutchik, NO! He’s with me, stand down, he’s with me!”

The shield comes flying at the monster’s face anyway—only to stop dead, still spinning, in midair an arm’s length away. Bucky catches a glimpse of his friend though he doesn’t want to look. Steve’s face is stricken white, all wide-eyed horror, limbs held tense. Fuck. Bucky’s stomach threatens to reject his last meal.

“Let him go,” Steve snarls.

Lurker snorts. He must send something into Steve’s mind, because Cap staggers, and then Steve’s face somehow becomes even more horrified and furious; he shakes his head defiantly.

“You’re lying,” Steve says, “no one owns him anymore. Bucky….”

Bucky shakes his head. “I can’t hear what he’s telling you but Steve, Lazutchik, _please,_ both of you stand down, no one here is Hydra—he’s not an enemy.”

Lurker swings his head back to peer at Bucky. _He seems to think you are his, but denies it. Are you_ certain _he is not with our captors?_

“No one’s less Hydra than Steve,” Bucky snorts. He pulls himself up to his feet, still hiding his nakedness behind the monster’s leg. The first part rings in his head like claxons: _he seems to think you are his._ Fuck, fuck, he can’t deal with this kind of information right now when he’s stark naked with spunk running down his legs.

“Bucky, what’s going on,” Steve calls, “what the fuck is this thing and what was it….”

What was it doing to you, he surely means. Bucky’s face burns. He slides around Lurker’s front and carefully takes the gore-stained, foxlike muzzle in both hands. “We go way back. Hydra captured him a few decades ago and at some point they gave me to him to try to get him to work for them. Today he broke loose, killed about two dozen goons, and was about to start ripping up SHIELD so I. I.” Say it, just say it. “I made a deal. Myself, like we used to, if he’d spare my friends. I think you...I think you came in on the tail end of me keeping up my end of the bargain.” He’s shivering, and has to squeeze his eyes shut to keep tears of shame from falling. “Don’t judge me, Steve. I have a _lot_ of useful skills and I fuckin’ used them.”

Steve takes a couple steps forward, but a warning growl from Lurker stops him in his tracks. “I don’t think I’ve processed this enough to judge yet. Bucky, be honest with me, was this your choice? Did this _thing_ hurt you?”

“It was my _idea,_ ” Bucky snaps. “Of course it fuckin’ hurt, I haven’t been fucked in three years and just _look_ at him. But it’s nothing I didn’t already know I can take.”

For a deeply uncomfortable moment, the three of them just stare at each other. After a beat of this awful silence Bucky mutters that he’s going to get his goddamn clothes on. Lurker sits down broadside, blocking the hall.

“I need that back.” He hears Steve say behind him, followed by the unmistakable _TANNG_ of the shield hitting the floor.

There’s still copious amounts of semen up his ass and all over his legs and groin, so it’s decidedly unpleasant having pants and boxers on. He’s lived through worse, he reminds himself with a sigh. Facing Steve is itself far worse. So he procrastinates, and takes Lurker’s muzzle in his hands again.

“You need to get as far away from this place as you can,” he tells the monster.

Lurker’s silver eyes fix on him, pupils narrowed. _My old offer stands, Shining Arm. You could come with me, and hunt in the snow and ice with me, and be my mate. I will keep you well fed and well fucked and will never cage you._

“You’re sweet,” he murmurs, smiling in spite of himself, “but I’ve got a home waiting for me.”

 _Hmm. You mean you have a mate waiting for you._ Lurker casts a very pointed glance at Steve, who’s just managing to hold himself together.

Bucky’s face burns, and he ducks his head. “It’s not like that.”

_And yet, he sweats jealousy at seeing me inside you. Your choice is your own, little one. I will miss you terribly again. Think of me when you pleasure yourself. The way I took you like no human ever could. Think of me on the solstice and how you could have spent those days on my knot, pregnant with my seed._

“Lazutchik,” Bucky chides, squirming.

 _I promise I will think of you. May we meet again someday._ Lurker nudges him gently with his nose, and licks his vulnerable neck, and turns to walk away. For a tense moment that leaves Bucky breathless, the monster and Steve face off, Steve looking like he’s still ready to throw down...but Lurker must have more to say to him, because the anger gets wiped right off his face in favor of a look of utter shock. It’s a look he turns on Bucky as the monster slithers off down the hall, presumably to the freedom of the taiga whence he came.

Now alone with his friend, Bucky can’t bring himself to look up, instead toying with his retrieved gun. “I didn’t want you to see that,” he says quietly.

“Sam warned me not to go after you,” Steve says, “but I’ve never been any good at not doing that.”

Bucky huffs a silent laugh. “Yeah. You’re kinda stupid like that.”

“I’m stupid alright,” Steve mutters, and strides right up to Bucky, and Bucky’s about to ask him what he’s doing and Steve is _kissing him_ and oh god his lips are so soft and Bucky

just

_breaks._

It feels like losing his mind. He whimpers against Steve’s mouth and deepens the kiss, bending backwards where Steve leans into him. Tears stream freely and he _sobs_ , unwillingly breaking the kiss.

Steve looks stricken again. “Was that wrong?”

Bucky sniffs, crying helplessly ,and clings to his arms. “No you idiot, I’ve been wanting that since we were kids. What did he _say_ to you?”

“That you need a mate to look after you and you turned him down so I’d better make my move. Why didn’t you say anything?” Steve swipes a thumb across Bucky’s cheek to wipe tears away.

”Same reasons as you probably,” Bucky sighs, “mostly being stupid and scared. We are both _massive_ idiots if it took you walking in on me getting fucked by a snow monster to get us together.”

Steve laughs, somewhat hysterically. “Yeah we really are. That...that’s gonna stick with me, I can’t lie.”

If Bucky’s losing his shit entirely, he figures he might as well go all out. “Look at it this way, I guess you know I like ‘em big.” It’s hard to sound sexy while crying, but what the heck.

“Good thing,” Steve rumbles, and oh shit, Steve Rogers is capable of sounding _salacious_ and Bucky is _into it_. But a moment later he’s back to looking concerned. “Can you walk?”

Bucky straightens up and wipes his eyes. “Yeah, I’m good. Gonna need a _thorough_ shower when we get back. Did you save me any Nazis to kill?”

Steve tightens the arm strap on his shield. “Should be some left. Let’s finish up this shitshow of a mission. You and I have a lot to talk about afterward.”

“Yeah,” Bucky says with a giddy smile, chambering a round and following Steve back towards the light, “we sure do.”


	3. Epilogue: A New Normal

**Summary for the Chapter:**

> Steve and Bucky explore each other. Intimately. Very, very intimately.

Bucky groans and tries as hard as he can to keep his body lax. The soft rope holding his thighs up is surprisingly comfortable thanks to Steve’s newfound skill in fancy trussing. That isn’t his favorite of Steve’s new skills, though.

“That’s it, sweetheart, take it deep for me,” Steve murmurs behind him. Bucky answers with a quivering moan as Steve’s broad, beautiful fist plunges back into the warm, lubed depths of his ass. His forearm is thick with muscle and stretches him wide, but if he can just relax enough he knows they can make it deeper still.

Bucky’s cock has perked back up already from his last orgasm. It’s hard, leaking, aching, bobbing up to smack against his belly and leaving pearls of precome splattered by its touch. His balls ache pleasantly, too, both from arousal and from the open-handed smacks Steve has laid down on the back of them. That’s not exactly helping him relax, but it feels so damn good.

He won’t be satisfied until Steve’s fingertips find the top of his descending colon. He wants it elbow-deep, and Steve, bless him, will give it to him. And if he asks for a second hand, he’ll get that too, so he asks, and squeals at the enormous pressure of having both in him at once. He gasps Steve’s name and then he’s coming again, hands fisting the sheets, asshole spread open wide around Steve’s thrusting forearm.

Steve is a very good partner: he gives Bucky a breather, but only a little one—never as long as he thinks he needs. Steve knows that no matter how much he whines about it, no matter how he chants “I need a minute, please, please stop, I can’t, I can’t,” he damn well can, and he will, and he’ll love it. The bell clutched tight in his right hand is testament to this: he holds it so it’s silent, and never lets it drop.

(There are times he does drop the bell, and Steve proves Bucky is right to trust him by stopping on the spot, whether it be to adjust for a cramp or because Bucky is truly done, or anything in between. A very good partner indeed.)

He’s drifting on a high, consumed by the depth and fullness of his beloved fisting him deep and fast. They test his limits with every thrust and he takes more and more and more. When at last Steve reaches the mark and tickles Bucky’s transverse colon, they stop to catch their breath, leaving Steve elbow-deep in Bucky’s ever-greedy cunt. Steve purrs praise and grinds them together while Bucky squirms and wails, and Steve puts his other hand inside to fill his rectum to the brim. Knuckles press and slide against his prostate and Bucky comes yet again—dry, shaking, balls empty and aching hard—until Bucky says the magic words: “Okay, that’s enough.”

“You did so well,” Steve croons at him, kissing and nibbling his ass as he carefully extracts first his off hand, then his arm and fist. He holds the open rim of Bucky’s wrecked asshole and hums appreciatively. “You wanna know what it looks like?”

“Yeah,” Bucky sighs, sagging into the rope.

“You’re gaping. It’s beautiful,” Steve tells him. “This sweet little pussy that used to be a cute little hole is wide open for all the world to see, like an invitation for anyone to come fuck you. I can fit my fingers in so easy—just like this.” He slips two fingers inside, then three, and there’s plenty of room for them; Bucky’s hole offers only the very weakest resistance to the intrusion. “It’s coming along nicely. Pretty soon I’ll be able to just bend you over and make you take my dick without any stretch at all because you’ll always be ready for it.”

Bucky’s dick makes a (rather pitiful) attempt to wake back up, but it’s too soon yet. “God, I want that. I wanna be ready for you all the time.”

Steve kisses his still-gaping rim. “Won’t be long now, sweetheart. We’ll have to be sure to give you my fist on the regular still, to make sure you don’t close back up on me. Staying ready for this dick takes practice. Speaking of which….”

Bucky wiggles his ass in invitation. “Do it, baby, it’s your turn, as hard as you want.”

“Good boy.” Steve kisses, then bites each ass cheek, and then shuffles up onto the bed behind him. He doesn’t bother lubing up his cock since Bucky’s so wet already from being fisted; he just grabs onto his waist and hammers his dick inside.

After Steve’s fist and forearm, a cock is no challenge, even a cock as big as Steve’s is, but it still feels real damn good. Bucky squeaks, purrs, and moans his pleasure as Steve sets a punishing pace that would leave a normal man bruised to hell. There’s no doubt Steve’s been hard for ages while punching Bucky’s guts and he’s giving it his all now that his cock is buried in that welcoming hole instead.

“God you’re so wet,” Steve pants, “wet and open for me. I love how much you love this. You love my cock, don’t you.”

“Yes,” Bucky whimpers, pushing his hips back as best he can without any real leverage, “yes, fuck Steve I love your cock so much, want it in me all the time!”

Steve takes a handful of Bucky’s long, sweaty hair, twirls it around his fist, and pulls, and fuck if Bucky wasn’t hard before he’s sure getting there now. “My good boy. Beautiful little cock slut. I owe you so many good hard fuckings for all the time we lost, don’t I?”

It’s hard to find words for a moment between the ecstasy of getting fucked hard and the wonderful sharp pain of having his hair pulled, but he manages. “Yeah you do, and I, oh, oh fuck yes, I owe you a lifetime worth of this ass however you want it.”

“I want it just like this.” With his free hand Steve cracks an open palm across Bucky’s ass and rubs the impact spot to make it color up faster. “Just like this, with you all tied up and dripping wet…and bent over every piece of furniture we own…and against every wall…in combat gear with our pants pulled down just enough to get inside you…I want you every single way I can get you.”

Bucky moans loud and pushes back. He doesn’t touch his cock; he wants to come just from being fucked again, wants to glow with pride and be bathed in Steve’s praise for coming on his cock from the sheer pleasure of penetration. “You can have me,” he pants, “anytime, anywhere, I’m yours, I’m yours, I’ll never be anyone else’s again.”

“ _Damn. Right._ ” Steve punctuates each word with an extra-hard thrust, powerful enough to bounce Bucky forward and jostle the air out of his lungs, and that does it, he has one last orgasm in him even if it’s dry and it feels like his entire body’s a firework going off. Steve fucks him right through it, relentless and deliciously greedy.

“Gonna mark you up, baby, gonna come inside you,” Steve tells him, and Bucky begs for it. A few thrusts more and Steve is pounding his load deep inside, groaning, squeezing Bucky’s hip hard enough to bruise even supersoldier skin, pulling his hair so hard he makes Bucky’s spine bow back towards him. Slowly now, he keeps sliding his dick in and out of Bucky’s ass as if unwilling to leave his lover’s body until he absolutely has to; and when he does pull out, he pushes the dribble of come that escapes back into that ruined hole. Ruined, or in their opinions, perfected.

Steve unties Bucky with sure, careful hands, and lays him out to massage his rope-bruised thighs. He kisses Bucky’s knees and sweaty skin, murmuring gentle praise and gently cleaning them both up. Bucky drifts in that warm and beautiful space he goes to in the rope until Steve’s loving ministrations lift him out of it, and he beams at his boyfriend, his lover out of time.

“You’re amazing,” Bucky croons. “Thank you.”

“ _You’re_ amazing,” Steve says, ducking his head. The absurdity of his sudden bashfulness makes Bucky giggle.

“Come here, I want to cuddle you senseless.”

Steve raises an eyebrow at him, but he’s smiling. “Fifteen minutes, and then we’re gonna shower.”

“We have a deal.”

_fin._

**Notes for the Chapter:**

> I thrive on feedback. The next “chapter” is just some illustrations and ecology of Lurker and his kind (including the sexy parts).


	4. Ecology of the Mindbeast

**Summary for the Chapter:**

> Some info and illustrations of Lurker’s kind. Including, naturally, the sexy bits.

Some fun (sometimes a little NSFW) facts about Lurker’s people, loosely known as mindbeasts:

They are fully sentient and sapient, but communicate very differently from any other natural species: in addition to body language and basic vocalizations such as growls and roars, they’re inherent telepaths.

Mindbeasts‘ telepathy is a two-way conveyance of intent, mood, and meaning that transcends words. Because of this and the fact that humans tend to speak aloud to them, they have the appearance of being able to understand any language.

In order to establish a telepathic connection, they must first pierce the psychic barrier of a target’s consciousness. Only trained psychics, including other mindbeasts, can effectively resist this.

While they are solitary, they do have a very loose society with their own primitive mythology and rules of engagement. When two mindbeasts meet it’s a tense affair. An attempt to establish a mind link is considered a polite gesture; resisting a link is a rude and aggressive one and indicates that the target intends to fight. If they don’t fight, they will most likely “fuck it out,” regardless of the sexes of either mindbeast, to redirect their tensions and tire them out so they can make a diplomatic decision about the territory dispute.

Mindbeasts do not assign names to themselves or others the way humans understand names, but use descriptive personal impressions instead. They do not have a name for their people. In fact, their lore holds that humans labor under the “curse of Adam,” a mythologization of the human drive to assign names and labels to themselves and everything and everyone around them.

Mindbeasts are ambush predators and obligate carnivores. They will eat anything rabbit-sized or larger; mostly they subsist on deer. They will gladly eat carrion, especially frozen, and often cache food in deep snow. As a rule they almost never hunt humans because the risk is greater than the reward; instead they try to frighten humans away from their territories, or simply abandon the territory if humans move in.

As natives of the taiga, they are well-adapted to frigid conditions. Their fur is double-layered, having a coarse, shaggy overcoat of guard hairs and a plush undercoat that traps air close to the body. Their toes and webbed and furred like those of a wolf, allowing them to run across or tunnel through snow with alarming speed.

In addition to formidable, bone-crushing jaws and sickle-shaped claws, mindbeasts have several psychic weapons at their disposal, depending on whether or not they’re skilled in a given talent. These include a paralyzing roar that wracks targets with pain in an area of effect; forming a telekinetic barrier that can fend off blows and weapons, even bullets; activating the adrenal gland of a target to trigger a fight-or-flight reflex, usually resulting in either terror or reckless aggression; and several others.

Mindbeasts couple for pleasure and stress relief year-round, but the females are only fertile for a 24-hour period on the solar solstices. Males begin to range out into other mindbeasts’ territories in advance of these days in hopes of finding a mate in time. Pairs will mate more or less non-stop (usually with naps in between) until the solstice ends at the following dawn. During this time frame, a male’s glans bulbis becomes active, making each coupling last anywhere from 15 minutes to an hour (the rest of the year, the glans bulbis is dormant, and sex involving males is much briefer). Pairs separate immediately once the solstice ends, with the visiting mindbeast driven out of the resident’s territory. Gestation lasts 16-18 months at the end of which a female whelps 1-4 kits. She will raise them alone for up to three years, teaching them to survive and honing their psychic talents.

Males have a pair of thin but strong tentacles stemming from either side of the prepuce (sheath). During coupling, these wrap around the thighs of the bottom (whatever their sex) to hold them in place without the use of claws.

Though rare, mindbeasts have a third sex: “decoy males,” who bear reduced genitals and posterior-positioned breeding tentacles that coil around a “regular” male’s thighs from below, and produce the same pheromones as a fertile female during solstices. Similar to decoy males of certain fish species, decoy male mindbeasts often intercept “regular” males to couple with them, sexually exhaust them, and sneak away to locate the nearest fertile female while the other male is recovering. Decoy males are known to adopt orphaned kits and raise them, whereas “regular” males show no interest in doing so. Notably, mindbeasts do not have gender roles and their ”language”, being nonverbal, has no pronouns, so there are no social strings attached to a mindbeast being one sex or another beyond the rearing of kits. In contrast to fish and bird species with a secondary male sex, mindbeasts’ sentience means that “regular” males know full well when they’re not mating with females, and they don’t seem to resent this; by their telling, the solstice drives them to breed, but only that, so a chance to tie with a decoy male is just as satisfying as tying a female.

They can and will happily mate with willing members of other species, including humans. The other creature/person may or may not survive this—especially with male mindbeasts, who present challenges both in terms of genital size and seminal volume.

Mindbeasts are long-lived. Humans don’t yet know HOW long-lived because mindbeasts’ understanding of math is very different from ours, but they’re thought to surpass a hundred years.

They are escape artists. To date no mindbeast has died in captivity because all captured specimens have escaped, whether by launching a psychic assault or by stealth.

The vision of a mindbeast is very keen, comparable to birds of prey. They’re capable of seeing into the infrared spectrum, giving them a sort of heat vision to navigate by in total darkness.

The mating tentacles at rest coil up into pouches in the creature’s belly skin, and unroll for use during sexual excitation. These tentacles are used to wrap around the thighs of the receiving partner to afford a grip without the more hazardous option of the forepaws’ claws. They’re covered in short fur and far stronger than they appear. Mindbeasts’ coupling often borders on violent, as it usually takes place when tensions are high, and these tentacles help prevent injury.

The testes are very large—comparable in proportion to swine and rodents. In those species this is an adaptation to a promiscuous lifestyle, while in the mindbeast it’s a solution to low fertility and the female’s somewhat labyrinthine vaginal tract. Semen production is prodigious, especially during the breeding period, in which a male may ejaculate 3 L of semen in a single coupling and then repeat the feat with about an hour’s rest, several times over.

Like most mammals, the mindbeast male has an os penis (penile bone) that enables penetration before the organ is fully erect. Full erection is reached just prior to orgasm. The average fully erect length of an adult male is 45 cm.

Two portions of the penis are especially sensitive: the bulbous, flanged glans which flushes deep red during arousal, and the penile flexure directly behind the glans bulbis where the vaginal vestibule or anus of the receiving partner closes around it once the glans bulbis is inserted.

The glans bulbis is a forked erectile gland that wraps around the penis near its base. Between breeding periods, the glans bulbis is inert. Sex therefore lasts about 10-30 minutes on average culminating a substantial ejaculation often lasting about a minute—and, ideally, one or several climaxes for the bottom. During the breeding period, the glans bulbis becomes activate; at the onset of ejaculation, it inflates and seals the participants together in a “tie“ that lasts an additional 15-45 minutes while the male ejaculates continuously.

When bottoming, a male will use his tentacles to stimulate his own penis, from coaxing it out of its sheath to constricting the knot and flexure. The prostate gland is located at just the right place to be stimulated by another male’s glans bulbis. Just as human men may prefer to top, bottom, or switch, mindbeasts have the same range of preferences, if fewer opportunities to indulge in them.

TL;DR, the tentacles rest coiled up in skin flaps but hold a bottom still during sex, their dicks are massive & get knotty on the solstice, they fuck like trucks, and come a ridiculous amount.

**Notes for the Chapter:**

> If you’d like to include mindbeasts in your fic, hit me up and I’ll be happy to fill in any gaps for you!

**Author's Note:**

> Wondering what exactly Lurker looks like? Check out [Chapter 4](https://archiveofourown.org/works/28335189/chapters/69423669) for illustrations and more info, then catch up with the rest of the fic!


End file.
